Discussion

The majority of juxta-articular cysts occur in the lumbar region, most commonly at L4-L5. They are associated with degenerative facetarthropathy and so they characteristically appear as an extradural round mass arising from the joint either in the posterolateral region of the spinal canal or in the paraspinal soft tissues (Fig. 4). Patients may experience radicular pain or other neurologic deficits depending on the location and size of the cyst.

Recognizing distinctions between synovial and ganglion cysts by imaging is usually not possible and not important clinically because the treatment is the same [1]. The main differential to consider is extruded disc material or a nervesheathtumor.